Better Ways to be Lazy: Applications to Glassy Matter

1. Better Ways to be Lazy: Applications to Glassy MatterA. Alan Middleton (Syracuse University) DMR 0606424 Materials are often disordered and complex, so it can be hard to predict their behavior. Computer scientists have studied how to count or find objects in a complicated environment and we apply those techniques. For example, techniques similar to those used by Google maps to find a short path can be used to find the lowest energy fracture line in a disordered material plate or the magnetic pattern in an alloy (upper right). Our group has recently computed the sizes of avalanches that take place in disordered magnetic materials as they are controlled by a magnet. We have also shown how magnetic memory effects can be simulated, using these techniques adopted from computer science to greatly speed up the simulations (lower right). Domain wall in a magnet = An efficient route Recent use of multiscale optimization: find best result in “patches” of different sizes, using algorithms modified from computer science, to simulate how domains grow (routes “best” on different lengths).

2. Better Ways to be Lazy: Applications to Glassy MatterA. Alan Middleton (Syracuse University) DMR 0606424 Our grant has allowed and encouraged the following broader impact activities, in the past year: * Visit classrooms to present demonstrations on states of matter (including liquid crystals). Co-organized a presentation to 250 middle school students. * Organized a workshop on Algorithms and Physics in Aspen, Colorado. * Extensive discussions on common problems with computer scientists. * Advised students, both graduate and undergraduate, with a wide range of backgrounds. Middle school students at SU Graduate Students: Rodriguez-Milla, Thomas